Configure IPv6 on your CentOS server

IPv6 was developed to counter the long-anticipated problem of IPv4 exhaustion. IPv6 is not only intended to replace IPv4 but also boasts of certain characteristics which are superior to IPv4 address like more efficient routing, directed data flows, simplified network configuration, security and much more.

Edit network file

# vim /etc/sysconfig/network

Add the following line at the end of the file.

NETWORKING_IPV6=yes

save & exit

If your interface is eth0, Then I would recommend you to create a new alias , so it will not cause any downtime.

So I have created a alias as eth0:3

vim /etc/sysconfig/network-scripts/ifcfg-eth0:3

Before proceeding this, You have better to edit the network config via your console or IPMI. So if anything goes wrong you can immediately revert the changes.